Iodoethane → (3R)-1,3-diethyl-6-fluoro-4-(4-methoxybenzoyl)-3,4-dihydroquinoxalin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of (3R)-3-ethyl-6-fluoro-4-(4-methoxybenzoyl)-3,4-dihydroquinoxalin-2(1H)-one (0.20 g, 0.61 mmol) in acetonitrile (5 mL) under nitrogen was added potassium carbonate (0.050 g, 0.36 mmol), cesium carbonate (0.11 g, 0.33 mmol) and iodoethane (0.15 mL, 0.29 g, 1.9 mmol). The reaction was stirred for 10 h at 50° C. and then 5 h at 63° C. The solvent was evaporated, and the residue was partitioned between ethyl acetate and water. The layers were separated and the organic layer was washed with water. The organic layer was concentrated in vacuo and purified via Biotage Horizon® (SiO2, gradient from 5% EtOAc/hexane to 33% EtOAc/hexane) to yield 0.21 g (96%) of (3R)-1,3-diethyl-6-fluoro-4-(4-methoxybenzoyl)-3,4-dihydroquinoxalin-2(1H)-one. MS (ESI) m/z 357 ([M+H]+); HRMS: calcd for C20H21FN2O3, 356.16090; found (ESI+), 357.16057.

Provenance & Evidence